Our investigations have evolved into a primary concern with granuloma formation not only in relation to schistosomiasis, but to granulomatous inflammation in general. This includes a horizontal approach involving bacteria, fungi, and foreign bodies as well as parasites, and a vertical approach that involves not only mechanisms of immunopathology but those of immunity as well. Our research objectives are divided into 6 areas: 1) The etiology and dynamics of the granuloma, including the role of egg secretions, the uptake of the secretions by host cells, the production of lymphokines by the cells and the source of the mononuclear cells that largely comprise the granuloma; 2) The further development of bentonite granuloma models to include the mechanism of the hypersensitivity granuloma, the study of granulomatous diseases of unknown etiology, and the introduction of a model for intracellular organism-induced granulomas; 3) The isolation, purification and characterization of the soluble schistosome egg antigens involving electrophoresis, molecular sieving and affinity columns, and testing of the isolated fractions for immunologic and biologic activity; 4) Nonspecific granuloma suppression, including suppression of immune complex injury, eosinophils, macrophages, and the immunosuppressive role of antischistosome drugs; 5) Antigen-specific granuloma suppression including the induction of tolerance and desensitization, and 6) Granulomatous inflammation around schistosome and ascaris larvae and its relation to immunity.